Are these paid shopping comparisons, or whatever Google finds itself and tries to usefully show to users? If it's the latter, your statement should read as follows:

If Google purports to be a search engine and then gives preferences to search results that benefit their users (making Google indispensable), it's ethically similar to an fiduciary adviser recommending things that make his clients rich (making himself indispensable). Being indispensible has its own benefits and value.